A street person or person of the street. These people usually dwell in cars that aren't theirs, warehouses, squatting holes, gutters, garbage cans, boxes, parks, opium dens, public bathrooms (bus/train station, airport), bushes, soup kitchen's, etc.
They can often be seen swimming in yuppie's pools in the daytime while the sell-outs are at work and carrying a bottle shaped brown paper bag.

Yuppie: get out of my way you bum!
Urchin: *pulls out urchin/hobo knife* I'm no bum, i'm an urchin! *stabs yuppie and steal his wallet for booze*
Urchin: *whistles tune* I love to live the urchin life, stabbin people with my urchin knife

Twin babies born into the life of the streets are referred to as "urchtwins". These urchin bretherin never seperate from eachother; they are together for life.
the most loyal of all mammals, the urchtwins knife yuppies and/or hookers that endanger the other half of their unit.

urchtwins are also the most lucky of all street people, for they are the only ones known to have kin.

-young female urchtwin is trapped in parking garage by drunken horny yuppie who is about to rape her-